Gray-Box Model Identification of an Integrated Plant with Recycle

The objective of this paper is to propose a systematic method for identifying a dynamic model of an integrated plant with recycle for plantwide optimization and control purposes. We are interested in cases where identification experiment is limited to a period of time much shorter than the plant’s settling time. The method is intended to take advantage of prior knowledge about the plant’s steady-state gains. We use an example of an integrated plant composed of a reactor and a distillation column to illustrate the potential issues and to test the effectiveness of the proposed gray-box identification approach.